Mozilla Firefox: Browser of Choice: Department of Silly Things 2004
I've been using Mozilla Firefox as a browser: they have an extension called "firesomething" which randomly changes the name of the program each time you start it. It is an utterly useless and silly extension but it makes me laugh. If you do a keyboard shortcut Ctrl+` (grave accent) in the browser window, you get a new name.
Examples: Spacedonkey, Seafox, Firesquid, Waterwolf, Superkangaroo, Powerimpala, Moonjackalope...
Even better: why not download it for yourself? It's easy to use and filled with silly goodness!